Add API to get the collision shape of a block before it's placed

paper-api/src/main/java/org/bukkit/block/data/BlockData.java

@@ -205,6 +205,19 @@ public interface BlockData extends Cloneable {
      */
     boolean isFaceSturdy(@NotNull BlockFace face, @NotNull BlockSupport support);
 
+    // Paper start
+    /**
+     * Calculates the collision shape this block data would have at a particular location.
+     * <p>
+     * This does not take into account any block updates that may occur if the block was to be actually placed in the world.
+     *
+     * @param location the location to calculate the collision shape at
+     *
+     * @return a {@link org.bukkit.util.VoxelShape} representing the collision shape of this block data.
+     */
+    @NotNull org.bukkit.util.VoxelShape getCollisionShape(@NotNull Location location);
+    // Paper end
+
     /**
      * Gets the color this block should appear as when rendered on a map.
      *